Background: In the period 27 December 2020 to 15 February 2021, about 29 400 of Norway's roughly 35 000 nursing home patients were vaccinated with the mRNA vaccine BNT162b2. During the same period, the Norwegian Medicines Agency received 100 reports of suspected fatal adverse reactions to the vaccine. An expert group has examined the reports and assessed the extent of a causal link between vaccination and death.
Material and method: The expert group worked in two pairs, each of which examined 50 anonymised reports. Each member first examined the reports alone and classified the causality as unlikely, possible, probable, certain or unclassifiable. Each pair then discussed their results until they reached a consensus. All four experts assessed a random sample of 20 reports. The degree of agreement was assessed using weighted kappa and McNemar's test of symmetry.
Results: The mean age of the patients was 87.7 years (range 61-103 years). Among 100 reported deaths, a causal link to the vaccine was considered probable in 10 cases, possible in 26 and unlikely in 59. Five were unclassifiable. Weighted kappa was 0.40 and 0.38 in the two expert pairs, respectively.
Interpretation: Most nursing home patients have a short remaining life expectancy, but vaccination may, in a few cases, have accelerated a process of dying that had already begun. Nursing home patients should still be given priority for vaccination, but the benefits versus risk must be carefully weighed up for the frailest patients.